WO2021194587A2 - Marine wake adapted rudder assembly - Google Patents
Marine wake adapted rudder assembly Download PDFInfo
- Publication number
- WO2021194587A2 WO2021194587A2 PCT/US2020/065893 US2020065893W WO2021194587A2 WO 2021194587 A2 WO2021194587 A2 WO 2021194587A2 US 2020065893 W US2020065893 W US 2020065893W WO 2021194587 A2 WO2021194587 A2 WO 2021194587A2
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- rudder
- insert portion
- forming
- marine
- blade
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
- B63H25/06—Steering by rudders
- B63H25/38—Rudders
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
- B63H—MARINE PROPULSION OR STEERING
- B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
- B63H25/06—Steering by rudders
- B63H25/38—Rudders
- B63H2025/388—Rudders with varying angle of attack over the height of the rudder blade, e.g. twisted rudders
Definitions
- the present invention is related to a component for watercraft and in particular, to a rudder assembly used for controlling the direction of movement of the watercraft.
- Rudders have been used for centuries to control the direction of watercraft traveling through water while under sail, while being rowed or towed, or while under power.
- Conventional rudder assemblies consist of a rudder blade fixed to a shaft, normally referred to as a rudder stock, located at the aft end of a boat or ship.
- the rudder is normally located directly behind the propeller and the rudder is turned about a vertical axis for steering control, either manually or by an electric or hydraulic mechanism which is attached to a lever arm or tiller located at the upper end of the rudder stock.
- rudder blades and rudder stocks have been built as welded assemblies with flat-plate rudder blades and airfoil shaped rudder blades being welded directly to the rudder stocks.
- Older rudder assemblies have also incorporated rudder blades that were bolted to the rudder stock through a flange, or palm piece, which is an integral part of the rudder stock.
- More modern rudder assemblies incorporated in higher performance military and commercial self-propelled ships are designed with a twisted shape having surfaces which are more precisely aligned with the water flow streams exiting the propeller. This more modern rudder shape typically reduces overall appendage drag on the ship and increases overall propulsive efficiency. These rudders are typically referred to as “wake adapted” rudders.
- Embodiments of the present invention improve upon the prior art by offering a design and process that allows the rudder stock and rudder blade to be manufactured separately and assembled after both parts have been cast and machined to their final dimensions and shape.
- An embodiment of the invention includes a rudder stock, for example manufactured from a high strength stainless steel alloy, and a rudder blade, for example manufactured from a high strength bronze alloy.
- the rudder stock is manufactured with a cylindrical upper shaft portion that is mounted to the ship through rudder bearings, and a tapered and slightly twisted lower section that is inserted into the rudder blade.
- the rudder stock can either be cylindrical or tapered to form an interference fit as described herein.
- the rudder stock is machined for the installation of one or more retaining bolts that are sized to withstand both the static and dynamic tensile loads of the rudder blade on the rudder stock.
- the rudder blade can be made from a solid casting or it can be made as a “cored” casting with hollow voids to reduce the overall weight of the rudder.
- the rudder blade is cast with a tapered and twisted cavity that matches the shape of the lower insert portion of the tapered rudder stock described above.
- This cavity is intentionally slightly larger than the tapered rudder stock by a nominal dimension of, for example about one-half inch, but this dimension can be revised if necessary through experimentation. This leaves an intentional gap between the rudder blade and the rudder stock along the entire length of the tapered portion of the rudder stock.
- the opening at the top of the rudder blade is cast to form a close fit with the diameter of the rudder stock, or this upper section can be machined to form a tapered mechanical or hydraulic interference fit.
- holes are either cast or machined into the blade to accommodate the installation of one or more retaining bolts or other fasteners.
- injection holes are machined into both sides of the rudder blade from the outside of the rudder into the bottom of the rudder stock cavity. After the rudder blade and rudder stock are assembled together using the bottom retaining bolts or other fasteners, the rudder is positioned vertically, and an epoxy-like cement or grout such as Chockfast, is injected into the rudder stock cavity through the injection holes and allowed to cure.
- Figure 1 is an elevational view of the rudder assembly in accordance with the present invention shown as a port side view.
- Figure 2 is an elevational view of the assembly of figure 1 shown in a front view.
- Figure 3 is an elevational view of the assembly of figure 1 shown in a rearview.
- Figure 4 is a detailed elevational view of the rudder blade showing internal features in phantom and showing certain components exploded from the assembly.
- Figures 5 and 6 are elevational views of the rudder stock component shown respectively in rear and side views.
- Figure 7 is an elevational side view of the rudder blade.
- Figure 8 is a cross-sectional view through the rudder blade of Figure 7 taken along lines 8-8 of Figure 7.
- Figure 9 is a cross-sectional view through the rudder blade of Figure 7 taken along lines 9-9 of Figure 7.
- Figure 10 is a cross-sectional view through the rudder blade of Figure 7 taken along lines 10-10 of Figure 7.
- Figure 11 is a cross-sectional view through the lower portion of the rudder assembly showing the lower portion of the shaft, the rudder blade and the chocking material.
- Rudder assembly 10 in accordance with an embodiment of the present invention is illustrated.
- Rudder assembly includes as principal components, rudder stock 12 and rudder blade 14.
- Rudder stock 12 is shown in more detail in Figures 5 and 6.
- Rudder stock 12 is in the form of an elongated element having an upper shaft portion 16 and a lower insert portion 18.
- Upper shaft portion 16 has a generally cylindrical outer circumference and is adapted to provide a structural connection with a ship’s steering system including associated torsional couplings which can engage features 19 formed at the top end of the shaft as shown in these figures.
- a ship’s steering system including associated torsional couplings which can engage features 19 formed at the top end of the shaft as shown in these figures.
- Upper shaft portion 16 also provides for mounting within suitable bearing elements for steering motion and further this portion is designed to restrain against the significant bending, vibration, cyclical, and shock loads applied to the rudder assembly during use.
- Lower shaft portion 18 has a twisted blade-like configuration which is adapted for closely fitting within central cavity 30 of rudder blade 14, as will be described further in detail as follows.
- the lower end of lower insert portion 18 features, in one exemplary embodiment, a pair of threaded bores 20 having a function which will be described in more detail later.
- FIGS 7-10 show additional features of rudder blade 14 which features leading edge 22, trailing edge 24 and bottom surface 26.
- Rudder blade 14 is, in the illustrated embodiment, a cast structure having internal voids for reducing weight and material requirements.
- the upper portion of the blade features three internal cavities including leading edge cavity 28, central rudder stock cavity 30, and trailing edge cavity 32.
- Central cavity 30 has an open upper end 33 and a blind (enclosed) bottom end 34.
- rudder blade 14 has a twisted configuration which provides improvements in propulsion efficiency as it cooperates with the thrust vortex created by the ships propeller (not shown) positioned immediately in front of rudder assembly 10.
- Rudder blade 14 in addition to having a twist along its vertical axis, is also tapered such that the leading edge cavity 28 in this embodiment grows smaller and disappears at the lower end of the blade.
- Figure 4 shows rudder stock lower insert portion 18 fit within central rudder stock cavity 30 of blade 14.
- the twisted blade-like configuration of the lower insert portion 18 follows the twisted contours of rudder stock cavity 30.
- a small radial gap 56 of uniform dimension is formed around insert portion 18 and the inside surface of rudder stock cavity 30.
- this radial gap 56 or separation distance measures approximately 0.5 inches, although the design gap would be a function of many variables.
- a mechanical attachment is provided at the lower end of insert portion 18 featuring bores 20 mentioned previously.
- a structural connection between rudder stock insert portion 18 and rudder blade 14 is provided in the form of mechanical fasteners such as screws 38.
- screws 38 are cast or machined into the rudder blade casting. Screws 38 pass through the bores to mesh with threaded bores 20. Once screws 38 are fully torqued in position, rudder stock insert portion 18 is clamped against the bottom of the rudder blade 24.
- This mechanical connection is provided for structural functions and further assembles the unit as a subassembly for subsequent fabrication steps.
- separate insert element 40 is provided having bores 21 which fits into a mating cavity 36 at rudder blade bottom surface 26.
- Screws 38 pass through shouldered bores 21 in insert element 40 and engage with threaded bores 20 of rudder stock 12. Additional fasteners may be provided to connect insert element 40 to rudder blade 14. Web 44 is provided between cavity 42 and rudder stock central cavity 30. [0034] In a preferred embodiment shown in Figure 11 , the upper portion of central rudder stock cavity 30 features shoulder 48 which closely conforms to the outer surface of rudder stock 12. Alternatively, an interference fit can be provided at shoulder 48 with rudder stock lower insert portion 18 to properly locate and secure the components of the subassembly. Moreover, this close or interference fit at shoulder 48 provides a sealed internal volume formed by gap 56. Figure 4 shows additional closure elements 50, 52 and 54 which enclose and seal internal cavities 28 and 32 within rudder blade 14.
- the subassembly of rudder stock 12 and rudder blade 14 is placed in a fixture and an injectable material, for example an epoxy compound such as ChockfastTM is injected to fill the void between rudder stock lower insert portion 18 and the inside surface of rudder stock cavity 30, shown as element number 58. Injection can be provided through injection hole 60 shown in Figure 4. It is preferred that the entirety of the internal volume formed by gap 56 is filled with the injectable material 58. This produces an integrated composite structure. Higher levels of torque can be transferred between rudder blade 14 and rudder stock 12 aided by the twisted configuration of the lower portion of rudder stock insert 18 and its close conformance with the inside surface of rudder stock cavity 30.
- an injectable material for example an epoxy compound such as ChockfastTM is injected to fill the void between rudder stock lower insert portion 18 and the inside surface of rudder stock cavity 30, shown as element number 58. Injection can be provided through injection hole 60 shown in Figure 4. It is preferred that the entirety of the internal volume formed by gap
- Injection holes 60 may be provided to facilitate the introduction of the injectable filler material 58.
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP20926521.4A EP4081381A4 (en) | 2019-12-23 | 2020-12-18 | Marine wake adapted rudder assembly |
US17/788,218 US20230027488A1 (en) | 2019-12-23 | 2020-12-18 | Marine wake adapted rudder assembly |
AU2020437827A AU2020437827A1 (en) | 2019-12-23 | 2020-12-18 | Marine wake adapted rudder assembly |
CA3162743A CA3162743A1 (en) | 2019-12-23 | 2020-12-18 | Marine wake adapted rudder assembly |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US201962952831P | 2019-12-23 | 2019-12-23 | |
US62/952,831 | 2019-12-23 |
Publications (2)
Publication Number | Publication Date |
---|---|
WO2021194587A2 true WO2021194587A2 (en) | 2021-09-30 |
WO2021194587A3 WO2021194587A3 (en) | 2021-11-25 |
Family
ID=77892499
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2020/065893 WO2021194587A2 (en) | 2019-12-23 | 2020-12-18 | Marine wake adapted rudder assembly |
Country Status (5)
Country | Link |
---|---|
US (1) | US20230027488A1 (en) |
EP (1) | EP4081381A4 (en) |
AU (1) | AU2020437827A1 (en) |
CA (1) | CA3162743A1 (en) |
WO (1) | WO2021194587A2 (en) |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
USD994575S1 (en) * | 2020-05-06 | 2023-08-08 | April Cottle | Rudder |
Family Cites Families (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1900011A (en) * | 1931-06-23 | 1933-03-07 | Harold L Durham | Corrosion preventing attachment for boats |
DE2555098C2 (en) * | 1975-12-08 | 1977-10-13 | Willi Becker Ingenieurbüro, 2000 Hamburg | Rudders, in particular balance profile rudders with one fin, for watercraft |
US4683830A (en) * | 1981-05-29 | 1987-08-04 | Hydroconic Limited | Ship's steering systems |
DE3441017A1 (en) * | 1984-11-09 | 1986-05-15 | Vladimir Isaakovič Drut | Method of assembling ship steering gear |
JPH0445998Y2 (en) * | 1985-04-02 | 1992-10-28 | ||
FR2693701B1 (en) * | 1992-07-16 | 1994-09-02 | France Etat Armement | Safran for medium and large tonnage ships. |
JPH07132889A (en) * | 1993-11-11 | 1995-05-23 | Yamaha Motor Co Ltd | Structure for small ship rudeer |
US6227131B1 (en) * | 1997-05-19 | 2001-05-08 | Tides Marine, Inc. | Sailboat rudder having a monocoque structure |
DE20314325U1 (en) * | 2003-09-16 | 2005-01-20 | Abeking & Rasmussen Schiffs- Und Yachtwerft (Gmbh & Co) | Hull attachment for a watercraft |
DE202005013583U1 (en) * | 2005-06-30 | 2005-11-03 | Becker Marine Systems Gmbh & Co. Kg | Rudder stock for water craft, has end sections made of wrought iron, and middle stock section connected with end sections and made of carbon fibrous composite or graphite fibers, which form middle stock section in the form of windings |
DE202007012480U1 (en) * | 2007-09-05 | 2007-11-29 | Becker Marine Systems Gmbh & Co. Kg | Oars for ships |
DE202007016164U1 (en) * | 2007-11-16 | 2008-01-24 | Becker Marine Systems Gmbh & Co. Kg | High efficiency rudder for ships |
DE102009022989A1 (en) * | 2009-04-01 | 2010-10-14 | Becker Marine Systems Gmbh & Co. Kg | rudder |
KR101281100B1 (en) * | 2011-05-19 | 2013-07-03 | 삼성중공업 주식회사 | Rudder and method for manufacturing the rudder |
KR101291176B1 (en) * | 2011-09-02 | 2013-07-31 | 삼성중공업 주식회사 | Rudder for ship |
KR101137816B1 (en) * | 2011-12-07 | 2012-04-18 | 주식회사 엠에이시에스 | Rudder for ship |
KR101181799B1 (en) * | 2012-02-07 | 2012-09-11 | (주)대성마린텍 | Rudder for ship |
KR101485255B1 (en) * | 2013-07-30 | 2015-01-21 | (주)대성마린텍 | Rudder for ship |
US9463588B2 (en) * | 2014-02-07 | 2016-10-11 | Todas Santos Surf, Inc. | Surf fin including injection molded pre-impregnated composite fiber matrix inserts |
CN204775970U (en) * | 2015-06-17 | 2015-11-18 | 上海红双喜游艇有限公司 | Novel rudderstock |
KR101760360B1 (en) * | 2015-08-03 | 2017-07-21 | 주식회사 제이에프코리아 | fiber reinforced plastic rudder and manufacturing method the rudder |
KR102024176B1 (en) * | 2019-06-11 | 2019-09-23 | 이상욱 | Manufacturing method of twisted type rudder |
-
2020
- 2020-12-18 EP EP20926521.4A patent/EP4081381A4/en active Pending
- 2020-12-18 AU AU2020437827A patent/AU2020437827A1/en active Pending
- 2020-12-18 WO PCT/US2020/065893 patent/WO2021194587A2/en unknown
- 2020-12-18 US US17/788,218 patent/US20230027488A1/en active Pending
- 2020-12-18 CA CA3162743A patent/CA3162743A1/en active Pending
Also Published As
Publication number | Publication date |
---|---|
WO2021194587A3 (en) | 2021-11-25 |
US20230027488A1 (en) | 2023-01-26 |
CA3162743A1 (en) | 2021-09-30 |
EP4081381A4 (en) | 2023-12-06 |
EP4081381A2 (en) | 2022-11-02 |
AU2020437827A1 (en) | 2022-07-21 |
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